Saturn's moon Titan observed using the polarimetric mode of SPHERE

Titan's atmosphere has a thick layer of haze which is reflecting the visible light from the Sun. Therefore, unlike in the near-infrared, we cannot see down to the surface and Titan looks like a featureless sphere of haze (left). However, the light scattered from the haze is highly polarised, like the blue sky of the Earth. The SPHERE instrument is equipped with sensitive polarimeters, which can measure how strongly the light is polarised (right). There is strong polarisation at the limb of Titan due to scattering by haze particles. This polarimetric technique will be used by SPHERE for a sensitive search for reflected, and therefore polarised, light from exoplanets.